Yesterday, I thought I could manage correctly the colors of my drawing. To-day, after opening a new session, all my "Black/White" layers are back to white and hatch area have colors with some variations. I spend nearly 2 hours restoring correct values. I would appreciate if a next release of QCAD would have an option to specify that colors must be kept as stored before and that Black/White layers are kept in one color to specify : either black, either white.

QCAD should of course not change any of the entity or layer colors when a drawing is loaded or saved. Only the display of colors can be adjusted automatically to prevent black on black / white on white visualization of entities.

Switching this option off should give you exactly what you want: fixed colors, what you see is what you get.

Please note that there is no 'Black/white' color in QCAD or DXF/DWG. QCAD 2 used this possibly misleading notion to indicate that the color display is adjusted when drawing black on black or white on white.

Another thought I'm having: Could it be that you are using an older version of the DXF / DWG format? If so you might want to use a newer version instead (File - Save As, choose version at the bottom). Older versions of DXF/DWG use a fixed color palette, so colors might be 'rounded' to the nearest available color when saving a drawing for example to DXF R12.

I'm using recent version of files at least if I can rely on QCAD 2 original files. QCAD 3 manages its format.As Black and custom colors are "auto corrected" de facto each time I save a Q3 file, I can't work on my drawings with QCAD rc5 with enough reliability. Standard non Black/White colors are the only ones preserved, eg Magenta, Blue.That's why I've prepared a bug report.